export component MainWindow inherits Window {
  height: 300px;
  width: 300px;
  property <[color]> colors : [#ff9d9d,#fff,#c4c4c4,#111,#444] ;
  for color[index] in colors:  Rectangle {
    height: root.height;
    width: root.width / colors.length;
    x:self.width *  index; 
    background: color; 
  }
}